Beyond the Quantum

          @misc{ pirsa_PIRSA:09100103,
            doi = {10.48660/09100103},
            url = {https://pirsa.org/09100103},
            author = {Valentini, Antony},
            keywords = {Quantum Foundations},
            language = {en},
            title = {Beyond the Quantum},
            publisher = {Perimeter Institute},
            year = {2009},
            month = {oct},
            note = {PIRSA:09100103 see, \url{https://pirsa.org}}
          }
          

Abstract

According to hidden-variables theories, quantum physics is a special 'equilibrium' case of a much wider 'nonequilibrium' physics. We describe the search for that wider physics in a cosmological context. The hypothesis that the universe began in a state of quantum nonequilibrium is shown to have observable consequences. In de Broglie-Bohm theory on expanding space, relaxation to quantum equilibrium is shown to be suppressed for field modes whose quantum time evolution satisfies a certain inequality, resulting in a 'freezing' of early nonequilibrium for these particular modes. For an early radiation-dominated expansion, the inequality implies a corresponding physical wavelength that is larger than the (instantaneous) Hubble radius. These results make it possible, for the first time, to make quantitative predictions for deviations from quantum theory. We consider, in particular, corrections to inflationary predictions for the cosmic microwave background, and the possibility of finding relic cosmological particles that violate the laws of quantum mechanics. (Reference: De Broglie-Bohm Prediction of Quantum Violations for Cosmological Super-Hubble Modes, http://arxiv.org/abs/0804.4656.)